JP3789697B2 - Flow injection analyzer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique that enables a plurality of different components to be analyzed simultaneously by introducing a sample solution once in an analyzer using a flow injection method.
[0002]
[Prior art]
In boiler water supply systems, etc. of power generation facilities, if metal components such as iron or copper are deposited or dissolved in the water supply, they adhere to boilers, turbines, piping, etc. and deteriorate them, hindering power generation. The amount of metal components in the boiler feed water must be strictly controlled because it may come.
[0003]
Therefore, flow injection analysis is used as one method for detecting the amount of metal components such as copper and iron.
[0004]
In this flow injection analysis, a sample solution containing a component to be detected is flowed into a capillary at a constant flow rate, and a chemical solution is injected into the segment to cause a color reaction, for example, at the contact portion between the two in the capillary. The component concentration of the sample solution is analyzed by detecting the degree with a downstream spectroscopic detector or the like.
[0005]
FIG. 6 is a diagram for explaining the principle. The collected sample solution is first fed to the pretreatment section A, where it is subjected to processing such as ionization by dissolution of suspended components precipitated in the sample solution, adjustment by reduction or oxidation, etc., and analysis section B Sent to. In the analysis unit B, a certain amount is cut out by the sample cutting unit 51 and fed to the narrow tube 52. The narrow tube 52 is supplied with a carrier solution at a constant flow rate by a carrier pump 53, and a sample solution is injected into the flow into a segment. And, in the middle of this narrow tube 52, other chemical solutions for pH adjustment, color reaction, etc. are intermittently injected by one or a plurality of chemical solution injection pumps 54a, 54b, 54c,. These chemical solutions are injected into the sample solution in segments. Reference numeral 55 denotes a detector composed of an absorptiometer or the like, and the concentration and the like of the component are detected by transmitting light of a specific wavelength through the sample solution that has undergone a color reaction and checking the degree of absorption. Then, the detected content is taken out as an electrical data signal, processed by a later processing unit (not shown), and displayed / recorded.
[0006]
[Problems to be solved by the invention]
However, in the conventional flow injection analysis, when two or more components are included in the sample solution and analyzed, when this is performed with one apparatus, the sample solution is collected in multiple times and collected. Each time the analysis target is changed, it is necessary to switch the chemical solution, switch the wavelength of light of the detector, and the like, which is inefficient. Moreover, when analyzing simultaneously, it was necessary to prepare several similar analyzers.
[0007]
An object of the present invention is to provide a flow injection analyzer that solves the above-described problems by allowing a sample solution to be introduced into a single device once to enable simultaneous analysis of a plurality of components. .
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the first invention is a flow injection method in which the sample solution introduced is cut in a predetermined amount and sequentially divided into a plurality of narrow tubes and the sample solution in each narrow tube is independently flow-injected. An analysis unit having means for analyzing by :
A pre-processing unit that is provided upstream of the analysis unit and adds a treatment such as dissolution, oxidation, and reduction to the introduced sample solution,
The pretreatment unit includes a cutout unit that cuts out a predetermined amount of the sample solution by a first carrier solution, and the cutout sample solution fed from the pretreatment unit by the cutout distribution unit of the analysis unit and The flow injection analyzer is characterized in that the sample solution is cut out so as to include a part upstream and a part downstream, and sequentially distributed to the narrow tubes of each system by the second carrier solution.
[0011]
According to a second invention, in the first invention, a double plunger type reciprocating pump is used as a chemical solution injection pump in the analysis unit, and different chemical solutions are injected into the narrow tube with a phase difference of 180 degrees.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a system diagram of a flow injection analyzer for explaining the principle of the present invention. Here, the sample solution processed in the pretreatment unit A is introduced into the analysis unit B to perform flow injection analysis. This analysis unit B includes two systems of reaction analysis units, and a sample solution alternately cut by a predetermined amount by the sample cut-out distribution unit 13 is segmented into the capillary tubes 11 and 12 of each system into a carrier solution (not shown). ). Various chemical liquids are intermittently injected into one thin tube 11 by chemical solution injection pumps 14a, 14b, 14c,..., And the other thin tube 12 is separated by another chemical solution injection pumps 15a, 15b, 15c,. These various chemical solutions are injected intermittently. Reference numeral 16 denotes a detector, which analyzes a target component from the degree of absorption at a specific wavelength of the sample solution flowing through the thin tubes 11 and 12. If different wavelengths are required at this time, two types of light having a desired wavelength are extracted from one light source and used.
[0013]
As described above, in this embodiment, since the sample solution is alternately distributed and fed to the two systems of narrow tubes 11 and 12 at regular intervals, different components can be analyzed independently by introducing the sample solution once. At this time, there is no influence between each system.
[0014]
FIG. 2 is a system diagram in which the present invention is applied to a flow injection analyzer for analyzing copper and iron deposited in boiler feed water. In the pretreatment part A, 21 is a first carrier solution supply pump, which feeds a first carrier solution (for example, pure water) a supplied from two pipes. Reference numeral 22 denotes a sample cutoff valve for cutting out the sample solution b collected from the boiler feed water and fitting it into the carrier solution a in a segment shape, and has a sample loop 22a for cutting out a certain amount. Reference numeral 23 denotes a solution pump, which injects a solution (for example, hydrochloric acid) c supplied from two pipes downstream of the sample cutoff valve 22. Reference numeral 24 denotes a melting portion that uses microwaves as heating energy, and is configured so that the solution passes through the electric field energy concentration portion in the microwave cavity resonator. Reference numeral 25 denotes a cooling unit provided downstream of the dissolving unit 24, and feeds the solution d that has been cooled to a predetermined temperature to the pipe 26.
[0015]
In the analysis unit B, 31 cuts out a certain amount of a region completely containing the sample solution part of the solution d fed from the pretreatment unit A, and then a second carrier solution (for example, 0.18 mol hydrochloric acid) e1, e2 Is a 16-valve type sample cutting / distributing valve that alternately distributes and pushes between the first thin tube 32 and the second thin tube 33, and has sample loops 31a and 31b for a certain amount of cutting. Reference numeral 34 denotes a second carrier solution supply pump that feeds the second carrier solution e to the sample cut-off distribution valve 31 by dividing it into e1 and e2. 35 is a chemical solution injection pump that alternately and intermittently supplies a copper color developing solution f (for example, DTCS) and an iron mask chemical solution g (for example, tartaric acid) to the first capillary 32, and 36 is an iron reducing chemical solution h (for example, hydroxylamine hydrochloride). ) And an iron coloring chemical solution i (for example, TPTZ) are alternately and intermittently supplied to the second thin tube 32, and 37 is a PH adjustment chemical solution j (for example, ammonium acetate buffer solution) that is supplied to the first pipe 32 and the second pipe 32. This is a chemical injection pump that alternately and intermittently supplies the piping 33.
[0016]
The first pipe 32 is provided with an injection point in the downstream direction in the order of the chemical liquid j for adjusting the pH, the chemical liquid g for the iron mask, and the chemical liquid f for copper coloring, and the reaction is performed downstream of the injection of the chemical liquid f for copper coloring. A coil 38, a detector 39, and a back pressure coil 40 are sequentially provided. The second pipe 33 is provided with an injection point in the downstream direction in the order of the iron reducing chemical solution h, the iron coloring chemical solution i, and the PH adjusting chemical solution j, and downstream of the PH adjusting j injection point. The detector 41 and the back pressure coil 42 are sequentially provided.
[0017]
In the above, the pumps 21, 23, 34 to 37 are all double plunger type reciprocating pumps, and solutions supplied in two systems to the input side are intermittently intermittently to the output side of the two systems with a phase difference of 180 degrees. To supply. The detectors 39 and 41 select light having the same or different wavelength from light emitted from a common light source and use it as detection light. Here, the reaction solution is transmitted and depends on the degree of absorption. Perform component analysis. The signals detected by the detectors 39 and 41 are processed by an arithmetic processing unit (not shown) and used for display / recording.
[0018]
Now, as shown in FIG. 3 (a), the sample cut-off valve 22 of the pretreatment section A has openings 2-3, 4-5, and 6-1 communicating with each other in the first switching state. b is discharged to the drain via the sample loop 22a. Here, when switching to the second switching state as shown in FIG. 3 (b), the openings 1-2, 3-4 and 5-6 communicate with each other and are stored in the sample loop 22a in a certain amount. The sample solution b is pushed downstream by the first carrier solution a as it is.
[0019]
Therefore, by switching the sample cutoff valve 22 alternately between the first and second switching states at a predetermined cycle, the sample solution b having a predetermined length (amount) at a predetermined pitch is segmented in the first carrier solution a. It is pushed in the form of and fed.
[0020]
This sample solution b is mixed with the solution c fed by the pump 23 and then pushed in the direction of the dissolving portion 24 where it is dissolved by microwave heating. As a result, the suspension of the iron component and the copper component precipitated in the cut sample solution b is ionized. Then, after being cooled to a predetermined temperature suitable for a chemical reaction in the subsequent stage by the cooling unit 25, it is fed to the analysis unit B through the pipe 26.
[0021]
As shown in FIG. 4A, the sample cut-off / distribution valve 31 of the analysis unit B has openings 1-2, 3-4, 5-6, 7-8, 9-10, 11- in the first switching state. 12, 13-14, and 15-16 communicate with each other, the solution d is discharged to the drain through the sample loop 31 b, and the second carrier solution e 1 supplied from the second carrier solution pump 34 enters the first capillary 32. The second carrier solution e2 pushes the solution d in the sample loop 31a to the second capillary 33.
[0022]
Here, when switched to the second switching state as shown in FIG. 4B, the openings 16-1, 2-3, 4-5, 6-7, 8-9, 10-11, 12-13. , 14-15 communicate with each other, the solution d is discharged to the drain through the sample loop 31a, and the second carrier solution e1 supplied from the second carrier solution pump 34 converts the sample solution d in the sample loop 31b to the first. The second carrier e <b> 2 is fed to the second pipe 33 by being pushed into the narrow pipe 32.
[0023]
Therefore, if the sample cutting / dividing valve 31 is switched between the first and second switching states at a constant cycle, the solution d is alternately pushed into the first capillary 32 and the second capillary 33 by the second carrier solution e in a segment shape. Will be fed.
[0024]
Here, the sample cut amount (determined by the lengths of the sample loops 31a and 31b and the related pipe length) at the sample cut-off distribution valve 31 is the sample cut amount (the length of the sample loop 22a and the related pipes). 2 times (for example, for 400 μl), the sample solution in the solution d in the pipe 26 can be adjusted by adjusting the switching timing of the sample cutoff valve 22 and the switching timing of the sample cutoff distribution valve 31. The sample cutting / dividing valve has a length twice (for example, equivalent to 400 μl) including a length (for example, equivalent to 100 μl) before and after the length (for example, equivalent to 200 μl) of b ′ (the sample solution b dissolved in the solution c) It can be cut at 31 and alternately fed to the first and second thin tubes 32 and 33. That is, as shown in FIG. 5, the sample solution b ″ that completely includes the portion b ′ of the sample solution b cut out by the sample cut-off valve 22 can be cut out by the sample cut-off distribution valve 31. a ′ is a region where the solution c is mixed into the first carrier solution a.
[0025]
As described above, the sample solution b ″ distributed to the first tubule 32 is adjusted in pH by the injection of the chemical solution j, the iron ions are masked by the injection of the chemical solution g downstream thereof, and the copper color is developed downstream thereof. After the medicinal solution f is injected, the reaction reaches the reaction coil 38, where the reaction is accelerated, and the detector 39 detects the degree of absorption of the specific wavelength at the colored portion.
[0026]
On the other hand, in the sample solution b ″ distributed to the second thin tube 33, all of the iron ions Fe ²⁺ , Fe ^{3+ and the} like are unified and reduced to Fe ²⁺ by the injection of the chemical solution h, and the iron coloring chemical solution i is downstream thereof. After the pH is adjusted by the injection of the chemical solution j, the detector 41 detects the degree of absorption of the specific wavelength at the colored portion.
[0027]
The back pressure coils 40 and 42 give a predetermined back pressure to the liquid feeding pressure of the first and second thin tubes 32 and 33 to suppress the generation of bubbles that may be generated by the reaction.
[0028]
As described above, since the sample solution d pretreated in the pretreatment unit A is divided and analyzed in the analysis unit B into two systems for copper analysis and iron analysis, the sample solution is loaded into one apparatus. By introducing once, copper and iron can be analyzed simultaneously. In addition, since a double plunger type reciprocating pump is used as a chemical solution injection pump, two types of chemical solutions can be supplied by one pump, and the necessary number of pumps can be halved. Since it has a phase difference, when it is injected into the same tubule, it can be made non-pulsating, and furthermore, since the sample solution can be sandwiched between the drug solutions, the two can be reliably brought into contact with each other.
[0029]
In addition, although the example which analyzes copper and iron simultaneously was demonstrated above, it is not restricted to this, By changing the wavelength of the detectors 39 and 41 and changing a chemical | medical solution, a silica, phosphoric acid, zinc and Iron, zinc and copper, and other two components can be analyzed simultaneously. In addition, if the sample cut-off distribution valve 31 is replaced with a valve that distributes to three or more systems, three or more types of components can be analyzed simultaneously.
[0030]
【The invention's effect】
As described above, according to the present invention, the analysis of a plurality of components can be realized simultaneously by taking in the sample solution once for one apparatus. At this time, since the sample solution for individual component analysis is separated into independent separate systems, it is not necessary to pay special attention to the interference between systems in selecting a chemical solution. In addition, since the double plunger type reciprocating pump is used as a chemical solution injection pump, the number of necessary pumps can be reduced by half, and when injecting into the same capillary tube, no pulsation can be achieved. Since they can be sandwiched, the two can be reliably brought into contact with each other.
[Brief description of the drawings]
FIG. 1 is a system diagram of a flow injection analyzer for explaining the principle of the present invention.
FIG. 2 is a system diagram of a specific example of a flow injection analyzer.
FIGS. 3A and 3B are explanatory diagrams of switching of the sample cutoff valve 22 in FIG.
FIGS. 4A and 4B are explanatory diagrams of switching of the sample cut-off distribution valve 31 of FIG.
FIG. 5 is an explanatory diagram of the cut and sort of the sample cut and sort valve 31;
FIG. 6 is a diagram illustrating the principle of a conventional flow injection analyzer.
[Explanation of symbols]
A: Pretreatment unit, B: Analysis unit 11, 12: Capillary tube, 13: Sample cutting / sorting unit, 14a, 14b, 14c, 15a, 15b, 15c: Chemical solution injection pump, 16: Detector 21: First carrier solution supply Pump: 22: Sample cut-off valve, 23: Dissolution solution supply pump, 24: Dissolution unit, 25: Cooling unit, 26: Pipe 31: Sample cut-off distribution valve, 32, 33: Narrow tube, 34: Second carrier solution supply pump, 35, 36, 37: chemical injection pump, 38: reaction coil, 39: detector, 40: back pressure coil, 41: detector, 42: back pressure coil.

Claims (2)

An analysis unit having a cutting and sorting unit that cuts the introduced sample solution by a predetermined amount and sequentially sorts the sample solution into a plurality of capillaries, and a unit that independently analyzes the sample solution in the capillaries of each of the systems , and
A pre-processing unit that is provided upstream of the analysis unit and adds a treatment such as dissolution, oxidation, and reduction to the introduced sample solution,
The pretreatment unit includes a cutout unit that cuts out a predetermined amount of the sample solution by a first carrier solution, and the cutout sample solution fed from the pretreatment unit by the cutout distribution unit of the analysis unit and A flow injection analyzer characterized in that the sample solution is cut out so as to include a part upstream and a part downstream, and is sequentially distributed to the narrow tubes of each system by a second carrier solution . 2. The flow injection analyzer according to claim 1, wherein a double plunger type reciprocating pump is used as a chemical solution injection pump in the analysis unit, and different chemical solutions are injected into the narrow tube with a phase difference of 180 degrees.

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